Abstract:
A field experiment was conducted at the research farm of Sher-e-Bangla
Agricultural University, Dhaka, Bangladesh during the rabi season of 2007-08
to study the control of stemphylium blight (Stemphylium botryosum) of onion
for seed production through some selected fungicides, plant extracts and
micronutrients. The experiment was laid out in a Randomized Complete Block
Design (RCBD) with 3 (three) replications. An onion variety BAR! Piaj-l was
used in the experiment. Treatment of onion bulb followed by foliar spraying
with nine treatments comprising Rovral 50WP, Dithane M-45, Ridomil Gold,
Bavistin 50WP, Cupravit 50WP, Neem leaf extract and Alamanda leaf extract
along with micronutrients and Control were explored in the experiment. In in
vitro experiment (cup method) Rovral 50WP proved to be the best in
controlling the radial mycelium growth of Stemphylium botryosum. In field
condition, bulb treated with Rovral 50WP (0.2%) followed by foliar spraying
at 7 days interval starting from onset of the diseases minimized disease
incidence, severity and increased seed yield followed by Dithane M-45. Neem
leaf extract showed better performance than Alamanda leaf extract in
controlling Stemphylium blight of 'onion. The micronutrient along without
spraying of fungicides and plant extracts had significant effect compared to
control.
Description:
A Thesis
Submitted to the Faculty of Agriculture,
Sher-e-Bangla Agricultural University, Dhaka
in Partial fulfillment of the requirements
for the degree of
MASTER OF SCIENCE (MS)
IN
PLANT PATHOLOGY